Field of the Invention
The invention relates to pacing devices for gravity conveyors and, more particularly, toward a release for the pacing device and to a method for pacing individual vehicles of a gravity conveyor into a conveying means of the gravity conveyor that conveys in a paced manner.
Description of Related Art
A gravity conveyor is a conveyor that conveys objects mainly by way of gravitational force. The gravity conveyor thereby can include individual vehicles that move on the gravity conveyor free of connections amongst one another and convey objects. Individual vehicles of the gravity conveyor are thus mainly driven by gravitation (thus gravitational force). The individual vehicles are designed in a manner such that they are capable of conveying objects. An object that is conveyed by an individual vehicle can be understood as a conveying unit which is composed of an individual object or of several individual objects. The term “object” in the context of conveying by way of individual vehicles, includes the complete conveyed goods that are conveyed by an individual vehicle.
With a gravity conveyor, a conveying means can convey the individual vehicles on part-stretches. Thereby, the conveying means can move the individual vehicles in a direction with a component counter, which is to say opposite to the gravitational direction. Or the conveying means can move the individual vehicles in a direction with a component in the gravitational direction. Or the conveying means can move the individual vehicles in a direction without a component in or counter to the gravitational direction (thus, horizontally).
The conveying means, for example, can convey the individual vehicles in a changing direction. Thereby, optionally differently large components of the direction in and/or counter to the gravitational direction can be included or not.
The conveying means can optionally convey the individual vehicles partly counter to the gravitational direction. This, for example, can serve for transporting the individual vehicles to a defined height (thus, a defined distance to the ground, measured in the gravitational direction), wherein this height can be used for a conveying by way of gravitation and/or can ensure a certain spatial position of the individual vehicles, for example for a transfer of the conveyed objects. The conveying means thereby, in particular, engages onto the individual vehicle at least partly from below. Engaging “from below” is meant as engaging in a direction counter to the gravitational direction. Thus, the individual vehicle can lie on the conveying means and be moved and driven by the conveying means.
The conveying means can optionally convey the individual vehicles at least partly in the gravitational direction. This, for example, can serve for pacing the individual vehicles, although these could be driven at a higher speed in the gravitational direction by way of gravitation. In this manner, it is possible to control how many individual vehicles at which time and at which speed move through a certain section of the gravity conveyor. The conveying means thereby engages onto the individual vehicle at least partly from below. The individual vehicle can thus lie on the conveying means and be braked by the conveying means.
Individual vehicles of the gravity conveyor can thereby be transferred by way of pacing devices for example, to conveying means that convey the individual vehicles, for example, in a paced manner.
Such a pacing device is known for example from EP 1 299 298 B1. There, buffer stores are described, whose holding elements (or individual vehicles) are not released from the buffer store and transferred to a conveying-away drive (or conveying means) individually, but in groups. For this, means are described for forming holding element groups in the buffer store and means for releasing holding-element groups from the buffer store, wherein these means can be designed as one or also as two device parts. These means are disclosed in EP 1 299 298 B1 as pacing wheels as well as device parts that are designed separately from one another and are separately controllable.
The release means disclosed in the state of the art, such as pacing wheels or device parts have the disadvantage that the individual vehicles abruptly transmit their impulse onto the release means or onto the end of the buffer store, on running onto the release means or onto an end of the buffer store. The individual vehicles are thus abruptly braked. Such a sudden braking can be disadvantageous for the individual vehicles, for the objects conveyed with the individual vehicles, for a fastening mechanism of the conveyed objects on the individual vehicle, for the release means and/or for device parts of the pacing device or of the gravity conveyor connected thereto.
The abrupt impulse transmission can lead to material fatigue, for example. A greater wear can also result from this. A high noise formation can also be caused. The conveyed objects in the individual vehicles can become damaged. The conveyed objects can be dislocated—relative to the individual vehicles and/or relative to one another in the case of objects with several individual parts. In particular, the conveying means (and thereby in particular its driver devices for the individual vehicles and/or its drive) can also become damaged, adversely affected and/or worn.